Marteen, I used Vallejo Model air color and Winsor&Newton Galeria Acrylic.
It's a little complicate but as I started with this recipe, I follow it at each step of painting :
(From right to left on the picture)
Two coats of Vallejo Surface Primer (mix of 70 605 German Red Brown and 70 624 Pure red) ratio 50/50 - applied using an airbrush
One coat of Vallero Model Air 71.084 Fire Red mixed with Game ink 72 086 (ratio 50/50) - applied using an airbrush
Then three coats of Windsor&Newton Crimson with a little part of Burnt Umber - brushed, very diluted
and at the end three or four coats of Vallejo 71.084 Fire Red mixed with 71.003 Red (ratio 50/50) - applied using an airbrush
I think it's the Fire Red that gives the slightly darker color...
It's a little complicate but as I started with this recipe, I follow it at each step of painting :
(From right to left on the picture)
Two coats of Vallejo Surface Primer (mix of 70 605 German Red Brown and 70 624 Pure red) ratio 50/50 - applied using an airbrush
One coat of Vallero Model Air 71.084 Fire Red mixed with Game ink 72 086 (ratio 50/50) - applied using an airbrush
Then three coats of Windsor&Newton Crimson with a little part of Burnt Umber - brushed, very diluted
and at the end three or four coats of Vallejo 71.084 Fire Red mixed with 71.003 Red (ratio 50/50) - applied using an airbrush
I think it's the Fire Red that gives the slightly darker color...